Abstract
In this population-based retrospective cohort study, the Optum claims dataset was used to identify children <4 years of age with the diagnosis of nasolacrimal duct obstruction during the period 2003-2016. A total of 156,044 children were identified, of whom 16,538 (9.43%) underwent a surgical procedure. There was a downward trend for the frequency of all types of treatments but particularly for facility-based probings.